The BetaFpv "Cross" board has been a standard in the community for literally years. Since official discontinuation of this board there has been an outcry from the community, so we've convinced BetaFPV to produce another batch, just for TinyWhoop.com. Depending on the endurance of demand, this could be the final batch of this FC.
Almost all hardcore racers have relied on this board at some point in their racing career, and many top pilots still do. Technology is still pushing into the future, but this tried and true board has a level of reliability that is rarely seen in the industry.
Here's what BETAFPV has to say about it.
The ultralight F4 1S 5A AIO Brushless Flight Controller is back in stock with new and upgraded features. Compared to the previous version, the new board uses Serial ExpressLRS 2.4G instead of SPI ELRS 2.4G so that it can support ExpressLRS V3.0. We updated the FC with high-quality BMI270 gyro and BB51 ESC hardware. In addition, this new board supports the Betaflight Blackbox function.
This board is 0.8mm thick and comes with motor plugs that are not pre-installed. You'll have to solder them on yourself (it's easy!).
This flight controller now comes with the BT2.0 U-cable.
- Comes with a Serial ExpressLRS 2.4G receiver, which can be updated via Wi-Fi or Betaflight serial passthrough. It is convenient for pilots to flash any version of ELRS RX firmware and especially can flash ExpressLRS V3.0 without updating flight controller firmware.
- Built-in an 8MB flash memory chip dedicated to Blackbox logging. It’s an extremely powerful tool for tuning and troubleshooting an FPV drone.
- Integrated motor pin connectors, it is easy to install motors without soldering work.
- Particular design with only 3.6g ultralight weight, reasonable layout, and easy to build. With a 26*26mm mounting hole size, it is fully compatible with the whoop frame in the current market.
Specification of FC
- CPU: STM32F411CEU6 (100MHZ)
- Six-Axis: BMI270
- Built-in Receiver: Serial ExpressLRS 2.4G
- Receiver antenna: Line antenna
- FC Size: 30*30mm
- Mounting Hole Size: 26*26mm
- Firmware version: betaflight_4.3.1_BETAFPVF411 (ELRS)
- OSD: Built-in BetaFlight OSD
- Blackbox: 8MB
- Recommend VTX: >=200mW, like BETAFPV M03 350mW VTX or TBS Unify VTX
- Power Cable: 55mm, with BT2.0 connector
Specification of ESC
- Power supply: 1S
- Current: 5A continuous and peak 6A (3 seconds)
- ESC firmware: A_X_5_.HEX for BB51 BLHeli_S hardware
- Signal Support: D-shot150, D-shot300, D-shot600, Oneshot125, Multishot, PWM
The BLHeli_S firmware could support the BB51 hardware now. This board is powered by BB51 hardware. If you want to setup the ESC specification, please use the BLHeliSuite16714902A_Beta or ESC-Configurator.
- ESC-Configurator: https://preview.esc-configurator.com/
- Download BLHeliSuite16714902A_Beta here.
- Download the BB51 ESC firmware. Please choose A_X_5.HEX.
Note: BetaFlight Configurator, BLHeli Configurator, and Bluejay Configurator are invalid for the BB51 ESC now.
Diagram
Below is the diagram for Serial ELRS 2.4G RX.
Serial ELRS 2.4G RX
Serial ELRS 2.4G RX uses the Crossfire serial protocol (CRSF protocol) to communicate between the receiver and the flight controller board. So the Serial ELRS 2.4G RX is available to support upgrading to ELRS V3.0 with no need to flash Betaflight flight controller firmware. Enter binding status by power on/off three times.
- Plugin and unplug the flight controller three times;
- Make sure the RX LED is doing a quick double blink, which indicates the receiver is in bind mode;
- Make sure the RF TX module or radio transmitter enters binding status, which sends out a binding pulse;
- If the receiver has a solid light, it's bound.
The Serial ELRS 2.4G RX can be updated via Wi-Fi or Betaflight serial passthrough. Here is the way to update the Serial ELRS 2.4G RX firmware through passthrough.
- Turn off telemetry in the Betaflight configurator.
- Power cycle, while holding the Boot button to put the ELRS receiver into the bootloader.
- Open the Betaflight configurator, exit DFU mode, and make sure the Betaflight is disconnected from the flight controller.
- Flash using the Passthrough option in ExpressLRS Configurator.
Betaflight Firmware and CLI
F4 1S 5A AIO Brushless Flight Controller comes with the default firmware betaflight_4.3.1_BETAFPVF411 (ELRS) or betaflight_4.2.11_BETAFPVF411RX (Frsky). The default firmware for Serial ExpressLRS 2.4G RX version supports ELRS V2.4 RX.
Pay attention, For the Serial ExpressLRS 2.4G version, ONLY the newest Betaflight firmware 4.3.1 start to support this BMI270 gyro. For the SPI Frsky version, DO NOT flash the other firmware, otherwise, the RX will be lost in control at a very close range. We have already built our own firmware betaflight_4.2.11_BETAFPVF411RX for SPI Frsky RX version to support BMI270 gyro. Please check the below link to download the firmware.
Note: The RX RSSI values drop when the flight controller is installed on the quadcopter with HD digital VTX (Walksnail or HDZero). For example, the theoretical failsafe RSSI values for 250Hz packet rate are -108dBm. Actually, the RX will be possibly lost in control when the RX RSSI values reach about -92dBm.
Connecting External RX/HD Digital or Analog VTX
Both Serial ExpressLRS 2.4G RX and SPI Frsky RX version support external HD digital VTX or Analog VTX. Please note that the SPI Frsky RX version reserves an SBUS port and a UART port, which is available for the SBUS protocol receiver or other external receivers. You can refer to the below picture.
Package
- 1 * F4 1S 5A AIO Brushless Flight Controller (ELRS)
- 4 * M1.2x4mm Screws
- 4 Motor Plugs
- 4 * M1.4x5mm Screws
- 4 * Anti-vibration Rubber Dampers